title: Increasing ethanol titer and yield in a gpd1Δ gpd2Δ strain by simultaneous overexpression of GLT1 and STL1 in Saccharomyces cerevisiae.
abstract: We have investigated whether simultaneous modification of cofactor metabolism and glycerol in a strain of Saccharomyces cerevisiae can eliminate glycerol synthesis during ethanol production. Two strains, S812 (gpd1Δ gpd2Δ PGK1p-GLT1) and LE17 (gpd1Δ gpd2Δ PGK1p-GLT1 PGKp-STL1) were generated that showed a 8 and 8.2 % increase in the ethanol yield, respectively, compared to the wild type KAM-2 strain. The ethanol titer was improved from 90.4 g/l for KAM-2 to 97.6 g/l for S812 and 97.8 g/l for LE17, respectively. These results provide a new insight into rationalization of metabolic engineering strategies for improvement of ethanol yield through elimination of glycerol production.
authors.affiliation: Key Laboratory of Systems Bioengineering of the Ministry of Education, Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China, jywang@tju.edu.cn.
authors.forename: Jingyu
authors.initials: J
authors.lastname: Wang
authors.forename: Wen
authors.initials: W
authors.lastname: Liu
authors.forename: Wentao
authors.initials: W
authors.lastname: Ding
authors.forename: Guochang
authors.initials: G
authors.lastname: Zhang
authors.forename: Jingjing
authors.initials: J
authors.lastname: Liu
mesh_terms: D000431:Ethanol / Q000378:metabolism* / Q000633:toxicity; D005285:Fermentation; D005970:Glutamate Synthase / Q000096:biosynthesis*; D005990:Glycerol / Q000378:metabolism; D050536:Glycerol-3-Phosphate Dehydrogenase (NAD+) / Q000172:deficiency*; D026901:Membrane Transport Proteins / Q000096:biosynthesis*; D060847:Metabolic Engineering; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000201:enzymology*; D029701:Saccharomyces cerevisiae Proteins / Q000096:biosynthesis*
chemical_list: D026901:Membrane Transport Proteins; C470555:STL1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D000431:Ethanol; C568531:GPD1 protein, S cerevisiae; C568532:GPD2 protein, S cerevisiae; D050536:Glycerol-3-Phosphate Dehydrogenase (NAD+); D005970:Glutamate Synthase; D005990:Glycerol